Messages

11

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:56:56 PM »

the rest of the pictures

12

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:56:02 PM »

And these pictures are as much of the settings as I thought might be needed to start the troubleshooting process. If you want to see any other screens, just let me know and I'll go take pics.

13

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:54:21 PM »

These pictures show the position achieved by hitting the home key on the keyboard.

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General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:53:24 PM »

These pictures show the G54 X0Y0Z0 I set

15

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:51:14 PM »

Does the Z DRO reflect the ammount of drift ? Or does it stay at the programmed value ?

That is something I haven't noticed, I think I'll be running a test program this afternoon to check to see if the Z drift is visible on the DRO.

I took some pictures, first off are the shots showing the drive mechanisms. The first is the Y axis. The second is the Z axis. The third is the X axis and the 4th shows the driveshaft that runs underneath to move the other side of the gantry along the X axis.

16

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 01:07:28 PM »

My ideal is you calculate first, and use the axis calibration tool to check your answer is correct.

My X and Y are belt driven gears, my Z is a gear screw. I'll try to figure this out.

Mach 3 can then make allowances for tool diameter. All tools MUST be entered into the tool table, and the tool number selected correctly

I have a single spindle, each tool change is a new program to keep it simple and allow for the top of material to be referenced after each tool change. I have no tool info saved in Mach3, MasterCAM X2 takes care of all the tool offsets. However if the issue was with tool offsets, why is the X axis perfect and the Y axis out?

Wait a minute, where did your reply go jimpinder....

I agree with Hood about your Z axis - Is is Z moving, is is your table slightly out of true. I mounted a steel (6mm) plate on my table, and had the machine skim it true to the axis one evening. You can write the program and leave the machine to do it

The table not being level doesn't explain the 2nd picture above. That pocket was cut at one specified Z depth and it ended at a different level then it started. The Z is clearly "drifting" as the machine moves, what would cause that variance?

Your machine has two DRO readouts on your axis. One is machine co-ordinates and the other is program (or work) co-ordinates. When the machine co-ordinates button is lit, the display is machine co-ordinates, when not lit, program co-ordinates (and you can toggle between the two.
 
The machine MUST know where it is. There are two ways to tell it. (and you probably know all this)
One is have a set of home switches fitted. If you then press "Ref All Home" the table and the cutter will settle to these switches. The machine-cordinates will go to zero. The machine is happy - it knows where it is. Is is not likely that these home switches will be in a convenient position for useful work to take place, and therefore the table and cutter will need movng.
You can - as you seem to be doing, use an offset - and then tell the machine to go to it's new 0.0.0  position - now your machine-co-ordinates will show the offset, program co-ords will show 0.0.0 - and you can run your program.
Alternatively you can move the machine to a convenient position to start your program, ignore the machine co-ords, set the program co-ords to zero and start.
 
In Mach 3 machine co-ordinates can only be zeroed by using "Ref all Home". There is a problem in that if no home switches are connected, you can still "ref All Home" - but all that will happen is that the machine co-ordinates go to zero - whereever the machine happens to be. If there are no offsets set, I think it takes the program co-ordinates to zero too.
 
You may be finding (if you have not set up the homing switches) that this is causing your offsets to change, if you inadvertently zero the machine co-ordinates.

I'll go and take some pictures of the Mach3 screens to help troubleshoot what is going on, I'm really lost.

17

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 12:38:53 PM »

Make sure you dont have any scaling on the axis that is giving you problems.

Mach3 is showing no scaling on the main screens, but is there somewhere I should be checking that?

Check to make sure your "Spoiler Board" is sitting correctly on the bed and that it is running true with regards to your axis.

The table is out by a very small amount, which is why I decided to go with .050 break thru, that way it'll be really deep at the "high" end and shallow, but should still be right through at the low spots. That doesn't explain the picture with the roughly 6" pocket that has a single Z depth and the router cut the path while drifting on the Z.

Does your machine have homing switches? The answer to this question will determine how you will proceed with this.

The machine does have a homing setup, when I tap the home key on my keyboard, it moves up into a nice safe position. It's the G28 command that is in the NC code that is the concern I have.

18

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: June 09, 2008, 09:56:50 AM »

I wanted to revive this post as I have some serious problems with Mach3 and my CNC router manufacturer is no longer in existence. I'm on my own to troubleshoot this machine. I've included a picture of the entire machine for reference.

1) First off, I'm having some axis woes. I discovered that when ShopCAM installed and setup the machine initially, they never bothered to calibrate steps per pulse for each axis, so everything was being cut half an inch too big. Using a dial indicator, I used the Axis Calibration tool on the Mach3 Settings screen to set the X, Y, and Z axis dead on, with a repeatability of +/- .0005". When I run a program, which I did one with a 1/2" diameter bit and then a different program with a 1/4" diameter bit, the Y axis adds exactly 1/16" of an inch to the part, the X axis cuts perfect. That's axis problem number one.
2) Axis problem number two is what I would call Z axis drifting. To cut my part I specify the exact Z thickness of the part, and add .050 for breakthru, which is overkill, but the part still ends up with an onion skin once I get about 18" along the X axis. See the attached picture of a pocket that was cut where the bit should have been at the same Z depth the entire time, but it drifted. The other picture is of various cuts that were all specified in the code to be the exact same depth, but notice the variance, the further ones even lifting completely above the spoiler board.
3) I've unchecked the boxes relating to overwriting my G54, but if I shut off the machine for the night, it will make the G54 X0Y0Z0 match where ever the machine was sitting when it was shut off. Right now I just bring it to X0Y0Z0 before shutting it down. Is there another way to save the position? Also related is machine coordinates. Does the table not have exact machine coordinates that are fixed, always the same? I ask for two reasons. One the machine coordinates change each time the machine is shut down. And two, the other day, between running two parts, the exact same part, the table suddenly came up with a new value for G28 and instead of moving up and preparing itself to run the program, it dropped down to well below the table's surface, fortunately off the X and Y axis, so it was spinning in the air, but without a quick E-stop right then, it would have moved into cutting the actual table.

I have another issue, but I'll add that one in a bit.

 

19

General Mach Discussion / Re: Mach3 Release questions and the usual CV question

« on: May 29, 2008, 02:17:36 PM »

Thanks, I played with the feedrates and acceleration for all 3 axis to fine tune as much as possible. I ended up with:

X
feedrate = 400 in/min
acceleration = 60 in/min/sec

Y
feedrate = 400in/min
acceleration = 60in/min/sec (I could go faster on Y, but I thought it should be equal to the best i could get out of X?)

Z
feedrate = 40in/min
acceleration = 10in/min/sec

I'm just going to go with Exact Stop and forget CV mode then. I'm cutting $1000 a sheet aircraft honeycomb panels that have to be exact, rounded corners of any sort are unacceptable.

I believe my version of Mach3 is a lockdown version.

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General Mach Discussion / Mach3 Release questions and the usual CV question

« on: May 29, 2008, 09:31:34 AM »

Hello all,

I know the very rudimentary basics of how the CNC machine works. My specialty is AutoCAD and MasterCAM. Mach3 is totally new to me as well. Our CNC machine is a ShopCAM from Lindsay, ON and apparently they went bankrupt and are no longer in existence as of just this past week. So I'm on my own to troubleshoot the machine.

A little on my setup:

x150 y64 z7 router table
Colombo 7.5hp spindle
Microstep Stepper motors
 - X Vexta PK2913-F4.0A 2-Phase 1.8degree/Step
 - Y Vexta PK2913-F4.0A 2-Phase 1.8degree/Step
 - Z Vexta PK296-F4.5A 2-Phase 1.8degree/Step
Mach3 R2.0.037 running in Vista (which runs fine it seems)

My first area of confusion is this. When I first started the process of learning the machine I noticed that there was a much newer releases of Mach3, so I DLed it and installed it. The ShopCAM guy came by and was kinda upset that I had did that. He said that the newest release was no good and the machine wouldn't work right, so he reverted it back to the R2.0.0037 and ran some sort of driver tests (not sure what he did) to verify that the machine was ok.
Questions:
- Is that the case or should I be running the latest version to get the best results?
- If I do upgrade, how do I do that without losing any vital setup information like motor steps per pulse and that critical sort of info?

Me second area where I need assistance is with CV and rounded corners. I can only get the square corner cuts I want right now with Exact Stop, but I've been warned by my MasterCAM people that it is really hard on the CNC machine. They told me I needed to play with accel/decel curves to get what I want. I guess this pertains to my question about release versions as well.
- Does the latest version of Mach3 handle CV better than my older release?

Thanks for any assistance and if I need to provide anymore information to help clear my situation up just ask.

EDIT: Added the actual stepper motor specs.